Research aimed at developing and evaluating interventions to effectively treat and prevent HIV/AIDS disease has presented a myriad of statistical challenges. Hence, there is a great need in the medical community for biostatisticians trained with particular expertise in the field of AIDS/HIV. We propose to continue this AIDS Biostatistical Training Program, which will support four predoctoral students. The training program is structured to provide (i) a sound training in the foundations of biostatistical theory and applications, (ii) opportunities for academic enrichment in AIDS issues through special courses, AIDS biology projects, seminar series and journal clubs, and interactions with AIDS trainees from other disciplines, and (iii) collaboration with established AIDS researchers in the conduct of clinical, epidemiologic and methodologic biostatistical research in AIDS. The program will be centered in the Department of Biostatistics as well as other departments in the School of Public Health and Community Medicine and the School of Medicine. The academic component of the training program will emphasize the foundations of biostatistical theory and applications as well as specific coursework in the biology and epidemiology of HIV/AIDS disease. Most of the formal courses to be taken by the trainees are taught by members of the Biostatistics, Statistics and Epidemiology Departments. The existing curriculum will also be supplemented by new courses on methodologic issues in AIDS research and biostatistical consulting in STD/AIDS research. The trainees will also attend regular series of weekly biostatistics seminars, monthly AIDS Clinical Conference, and biweekly AIDS Journal Club. The research component of the training program will focus on collaboration in ongoing biostatistical methodology research in addition to significant involvement in one or more clinical research projects. The clinical research projects will be identified from ongoing studies in the HIVNET Statistical Center, the University of Washington Center for AIDS Research, the University of Washington International AIDS Research and Training Program, and regional biotechnology firms. Faculty in the Biostatistics Department actively participating in HIV/AIDS research will serve as preceptors and help the trainees integrate the knowledge and skills necessary to contribute to the multidisciplinary activity of clinical research in AIDS.